This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. xc2xa7119 from my application APPARATUS AND METHOD FOR GENERATING CONTROL VOLTAGE HAVING PHASE DIFFERENCE filed with the Korean Industrial Property Office on Jul. 9, 2001 and there duly assigned Ser. No. 40901/2001.
1. Technical Field
The present invention relates to the control of an electronic device such as an image displayer or a fly-back transformer (FBT) and, more particularly, to a control voltage generator which generates control voltages for controlling the electronic device. and a method for generating the control voltages.
2. Related Art
A control voltage generator generates control voltages, which have the same amplitude, the same frequency, and the same phase. and provides such control voltages to loads. Then, an electronic device adjusts the level of brightness or the level of a high voltage or a high current in response to the control voltages inputted into loads. If the control voltages are simultaneously provided to the loads, an excessive amount of current may flow into the loads. Accordingly, the electronic device having the control voltage generator may make noise, may malfunction, or may consume unnecessary power. For example, when the electronic device having the control voltage generator is an image displayer, a screen on which images are displayed may flicker. In addition, when control voltages having the same phase are simultaneously provided to the loads, the electronic device may make noise due to interference occurring between the loads.
To solve the above-described problems, it is a first object of the present invention to provide a control voltage generator which is capable of generating control voltages having different phases for controlling an electronic device.
It is a second object of the present invention to provide a method for generating a control voltage using the above control voltage generator.
Accordingly, to achieve the first object, there is provided a control voltage generator, which includes first thru N-th loads (where N is a positive integer no less than 2), and which is installed in an electronic device that may make noise or malfunction when signals having the same phase are simultaneously input into the loads. The control voltage generator includes: a sawtooth generator which generates and outputs a sawtooth signal; a first driving signal generator which compares the sawtooth signal generated by the sawtooth generator with an input signal having information as to the degree of variation in the level of a predetermined signal, which directly corresponds to a typical function of the electronic device, and which outputs the result as a first driving signal; and second thru N-th driving signal generators. Preferably, an n-th driving signal generator (where 2xe2x89xa6nxe2x89xa6N) compares the input signal with the sawtooth signal and outputs the result as an n-th driving signal. The first thru N-th driving signals are provided as control voltages to the first thru N-th loads, respectively, and the electronic device varies the level of the predetermined signal in response to the control voltages.
To achieve the second object, there is provided a method for generating control voltages, which have phase differences, using the control voltage generator. The method includes generating a sawtooth signal, comparing an input signal with the sawtooth signal. and generating first thru N-th driving signals with different phases.